1. Field of the Invention
The invention relates to a deep vibrator comprising a propulsion head vibrating in the horizontal direction via a driven eccentric, the propulsion head being secured to the lower end of a suspension tube while the outer wall of the suspension tube includes pipes arranged in the longitudinal direction thereof having at the lower end of the propulsion head a spraying nozzle through which water may be fed under pressure.
2. Description of the Prior Art
Deep vibrators are used in the construction of material columns in the ground, such as drainings, stop compressions, and concrete piles. To this end, the deep vibrator is driven with its propulsion head actuated by vibrations to the desired depth in the ground. Subsequently, the deep vibrator is withdrawn from the ground by means of a suitable tool while at the same time the proper filling material is filled through the deep vibrator into the hollow space so produced.
A deep vibrator having such features has been described in the journal "Baumaschine und Bautechnik", vol. 1957, no. 12, pp. 411-413. The deep vibrator described therein has a propulsion head which oscillates horizontally with respect to the longitudinal axis of the deep vibrator as it is being immersed into the ground. In this way, the propulsion head produces an annular space in the ground surrounding it, which is essentially free from ground material so that with the aid of its proper weight and the pressurized water ejected at its tip, the propulsion head may be immersed into the ground.
However, because of the annular space created around it, the oscillation of the propulsion head are not effectively transferred to the surrounding ground material as the deep vibrator is immersed. The ground material, therefore, is not pushed back sufficiently to allow an efficient immersion velocity.
French Patent Specification No. 1,277,369, discloses a deep vibrator, which vibrates vertically with respect to its longitudinal axis by means of a vibrator provided on its upper side. In order to avoid, or at least to reduce, adhesion of the deep vibrator to the ground material surrounding it when immersing it into, or withdrawing it from, the ground, pressurized water is radially ejected via openings provided in the casis of the device.
French Patent Specification No. 455,730 describes a similar device, wherein the body to be immersed is surrounded by a pipe cage in which spraying nozzles are provided.
The two latter devices are driven into the ground by vibrations in vertical direction. Therefore, no annular space is formed at the lower ends of these devices, which would facilitate an immersion of the devices into the ground.